It is possible to increase the network capacity of a basic service set (BSS) using Uplink (UL) Multi-user Multiple Input, Multiple Output (MU MIMO). With UL MU MIMO, multiple STAs are permitted to simultaneously (in time and frequency) transmit to a multiple-antenna access point (AP) and the resulting signals are separated by the AP's MIMO equalizer. Long training fields (LTFs) are used within preambles for channel estimation. With UL MU MIMO, long training fields (LTFs) sent from different STAs should form an orthogonal matrix such that the AP can differentiate them. STAs need to know how to form their preambles such that the combination of LTFs from different STAs at the AP can be differentiated. It is possible to increase the network capacity of a basic service set (BSS) using Uplink (UL) Multi-user, Multiple Input, Multiple Output (MU MIMO).
With UL MU MIMO, multiple STAs are permitted to simultaneously (in time and frequency) transmit to a multiple-antenna AP and the resulting signals are separated by the AP's MIMO equalizer. Long training fields (LTFs) are used within preambles for channel estimation. With UL MU MIMO, long training fields (LTFs) sent from different STAs should form an orthogonal matrix such that the AP can differentiate them. STAs need to know how to form their preambles such that the combination of LTFs from different STAs at the AP can be differentiated.
Thus, a strong need exists for systems, apparatus and methods to improve UL MU MIMO techniques.
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